In accelerating a speed of a generator equipment of a gas turbine or the like of a background art, a motor provided exclusive for starting and electric apparatus SFC (Static Frequency Converter) for using a generator as a motor are used. The apparatus are used only in starting, and therefore, in order to achieve a reduction in plant cost, the apparatus having capacities as small as possible have been used.
Therefore, in a current state, a revolution number is increased up to 30% of a rated revolution number by using the apparatus exclusive for accelerating a speed, thereafter, fuel supply is started and the revolution number is increased by an acceleration torque of the turbine per se.
However, according to the closed cycle gas turbine of circulating the working fluid in the closed system by using the atomic reactor or the like for the heat source, a temperature elevating rate is restricted by a restriction imposed on a reactor main body (for example, 100° C./h) and rapid temperature elevation is difficult. Therefore, according to a starting method using a starting procedure similar to that of the gas turbine of the background art, a problem that time is taken for elevating the speed of the turbine to the rated revolution number is posed.
On the other hand, according to a method of elevating a speed up to a rated revolution number by using only a starting apparatus, a capacity required for the starting apparatus is increased, and therefore, a problem of increasing plant cost is posed.
As a method of resolving the above-described problem, a technology of operating an amount of filling helium circulated in a closed system has been proposed (refer to, for example, the Publication of Japanese Patent No. 3020853).
According to a technology described in the Publication of Japanese Patent No. 3020853, by reducing the amount of filling helium more than a filling amount in a rated operation in accelerating the speed of the turbine, a drive torque required for elevating the speed of the turbine can be reduced and a capacity required for the starting apparatus can be reduced.
However, according to the technology described in the Publication of Japanese Patent No. 3020853, time is taken in operating the helium filling amount, and therefore, a problem that the technology is not pertinent for being used in an acceleration operation which is finished in a comparatively short time period.
Further, according to a speed reduction gear or the like for transmitting a drive torque generated by a motor or the like to a turbo unit comprising a compressor and a turbine, a drawback of fretting or the like is prevented from being brought about by being loaded with a necessary minimum torque.
However, when the drive torque required for accelerating the speed of the turbine is reduced as described above, also a torque loaded to the reduction gear or the like is also reduced to pose a problem that there is a concern of bringing about a drawback of fretting or the like by deviating load sharing of the gear from a standard value by a self weight of the gear, or shifting a contact position of teeth from a standard position.